Евалуација на ефектот од тироидна супституциона терапија на левовентрикуларната систолна и дијастолна функција кај супклинички хипотироидизам

Abstract

Introduction: Subclinical hypothyroidism (ScH) is defined as a condition with slightly increase in serum concentration of thyrotropin (TSH) with normal values of circulating thyroid hormones, free thyroxine (fT4) and triiodothyronine (fT3). Clinically manifest hypothyroidism is associated with systolic and diastolic dysfunction. Studies investigating systolic and diastolic left ventricle function in ScH have shown controversial results. Material and Methods: The study included 80 consecutive patients with newly diagnosed ScH and a group of 30 healthy, euthyroid patients as controls. Both groups were appropriate by: age, gender, body mass index and the number of women in menopause. Criteria for diagnosis of ScH were: TSH> 4,2mU/L, fT4 (10,3- 24,45pmol/L), and fT3 (4,2-8,1pmol/L). In all participants physical examination including measurement of blood pressure, body weight and height, assessment of blood TSH, fT4, fT3, antibodies directed to thyroid peroxidase (anti-TPO antibodies) and thyroglobulin (anti-Tg antibodies), lipid status, thyroid ultrasonography, M mode, 2D, Doppler, Tissue Doppler Imaging (TDI) and 2D speckle tracking echocardiography were done. All analyses in ScH patients were repeated after 5 months euthyroid state. Results: SCH patients were significantly different from their matched controls in the following parameters: higher TSH, lower fT4 and fT3, higher prevalence of symptoms of hypothyroidism and positive anti-TPO and anti-Tg antibodies, higher systolic blood pressure, higher volume and degree of hypohenicity of thyroid gland on ultrasound, higher mean values of total cholesterol, LDL-C, total cholesterol/LDLC, HDL-C/LDL-C, a shorter A dur., lower quotient E/a, higher MPI, higher quotient E/e 'sep., lower negative value of GLS, and lower S/TDI. TSH statistically significantly correlated with: positive anti-TPO antibodies, systolic blood pressure, triglycerides, total cholesterol, arterial pulse, thyroid volume and hypoechogenicity, EF, E/A, E/e 'sep., GLS, and S/TDI. TSH had a statistically significant independent influence on: EF, LVEDd, IVRT, MPI, GLS, and S/TDI. After 5 months euthyroid stage there were statistically significant improvement in the following parameters: total cholesterol, LDL-C, LVEDd, EF, E / e 'sep., A dur, MPI, and GLS. Conclusion: ScH was associated with hyperlipidemia, increased volume of the thyroid gland, and worsening of diastolic and systolic (global and longitudinal) left ventricle function. All these disorders were reversible after treatment with Lthyroxine.